Steller's Sea Cow – driven to extinction

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Background - 8 May, 2009

The Steller's sea cow (Hydrodamalis gigas) was a large sirenian mammal, which grew up to 10 metres long and weighed between 6 and 8 tonnes. It was discovered in 1741 near the Asiatic coast of the Bering Sea by German biologist Georg Steller, who was travelling with the explorer Vitus Bering. Just 28 years later, the species was extinct. It is the first recorded example of humans driving a marine species to extinction.

In November 1741, the weary crew of the Bering voyage, plagued by scurvy and hunger, were 5 months into their journey home from North America. They had all but given up on survival when they spotted an unknown island (Bering Island) and ran aground.

Initially the hungry crew fed on sea otters, which were so abundant hundreds could be found just 3 kilometres from their camp. Six months later, the crew had hunted so many otters that they were now forced to travel up to 40 kilometres over difficult terrain to hunt them. Facing another winter on the island, they began to look for alternative food sources. Soon sea cows replaced otters as the staple food in the crew's diet.

The following spring Steller and his companions built a new ship from the wreck of the old, and left Bering Island on August 14, 1742. Though forced to leave behind much of Steller's painstakingly gathered research, they nevertheless told the world about the sea cow. As the news of their travels initiated a 'gold rush' among adventurers seeking to profit from the newly-discovered lands, virtually all ships on their way to the new world stopped at Bering to load sea cow meat.

Just 28 years after it was first discovered, Steller's sea cow was extinct.

Today, archaeological evidence tells us that the sea cow was formerly widespread in the seas between Japan and California, long before Steller 'discovered' it. But overexploitation by indigenous peoples and loss of its kelp forest habitats had forced the species to a retreat in the Bering Sea.

Today, history is being repeated in the Bering Sea region. Another magnificent marine mammal, the Steller sea lion, is being pushed to the point of extinction. The sea lion and its close relative the northern fur seal are being starved of Alaska Pollock, their main food source. Alaska Pollock is heavily overfished by the world's largest single species fishery - primarily to provide whitefish fillets for the fast-food industry.